1. Field of the Invention
The present invention relates generally to sensor-based systems, and more particularly to a vehicle-mounted collision avoidance system which warns drivers of potential collisions.
2. Background Information
The roads are becoming more and more congested with vehicular traffic. As traffic congestion has increased, the number of accidents has also increased. Some of these accidents can be traced to driver inattentiveness or to the failure of the driver or of other drivers to see and react to surrounding vehicles.
Muth Mirror Systems of Sheboygan, Wis. manufactures a side view mirror with a built-in turn signal display (a “chevron”). The side view mirror can be mounted on both the passenger and driver sides of the vehicle and includes light emitting diodes (LEDs) which blink in time to the turn signal. The chevron is designed to be clearly visible to drivers in the lane adjacent to the host vehicle.
Such a display is good for warning drivers of adjacent vehicles. It does little, however, to warn the driver of the host vehicle of potential collisions.
Systems for warning drivers of objects external to their vehicle have been around for a long time. Mirrors, and sometimes combinations of mirrors, are being used to reveal locations hidden to the driver's view (i.e. “blind spots”). Mirrors, however, have a deficiency in that the driver can only look in one spot at any one time, and no one mirror can provide a complete view of all the possible blind spots. If they look in one mirror, see that the way is clear, start looking elsewhere and then a vehicle pulls into the area they thought was clear, they won't see it and may run into the vehicle. For example, if the driver looks at the lane adjacent to the vehicle, sees that the way is clear, starts looking elsewhere and then a vehicle pulls along side, the driver won't see it and may clip the vehicle while changing lanes.
In addition, mirrors don't work well in changing lanes, particularly in tractor-trailer rigs. One reason is that a side view mirror only looks in the lane adjacent to the vehicle and to the rear of the side view mirror. Vehicles forward of the side view mirror or more than one lane away from the vehicle may be missed. In addition, as soon as the rig begins to turn, the mirror that looked down along the side of the vehicle is directed into the side of the trailer and the driver is blinded to activity on that side of his truck.
Sensor-based warning systems have also been proposed. For instance, Sonar Safety Systems of Santa Fe Springs, Calif. has a rear-mounted sensor system based on a single sensor which detects objects in three distance zones from the rear of the vehicle. The system provides alarms and audible feedback that inform the driver whether the obstacle is close (Zone III), out a little farther (Zone II), or even farther out yet (Zone I).
What is needed is a system and method for automatically warning the driver of potential collisions at the front, to the sides and behind a vehicle.